Thomas lincoln



(No Model.)

. LINCOLN.

KEY. No. 289,284.. Patented Nov. 27, 1883.

N4 PETERS. Photo-Lit nn n nnnnnnnnnn nnnnnn c.

UNITED STATES PATENT OFFICE.

THOMAS LINCOLN, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE HOPKINS & DICKINSON MANUFACTURING COMPANY, OF SAME PLACE.

KEY.

SPECIFICATION forming part of Letters Patent No. 289,284, dated November 27, 18 83.

Application filed September 26, 1883. (No model.)

To a l whom it may concern:

Be it known that I, THOMAS LINCOLN, of Newark, New Jersey, have invented a certain Improvementin Flat Steel Keys, of which the following is a specification.

My invention relates to the method of centralizing flat steel keys in the key-hole bushings of looks.

It consists in providing such keys with a spline, which is inserted and fastened in a 1ongitudinalslot formed in the stem of the key opposite the bit, the key-hole bushing being longitudinally recessed to admit the spline.

The accompanying drawings, representing my invention, are as follows:

Figure 1 is a side View of the key-blank, showing the slot for the reception of the spline. Fig. 2 is a side view of the spline-blank. Fig. 3 is a View of the key with the spline-blank inserted and upset upon its opposite edges. Fig. 4 is a transverse section through the line X X on Fig. 3; Fig. 5, a similar section, showing a modification of the spline. Fig. 6 is an elevation of a portion of a lock, showing the key hole bushing fitted to receive my improved key. Fig. 7 is a longitudinal section of the stem and spline, showing a modification n the manner of fastening the spline.

The drawings show a flat ,steel key made by stamping the blank represented in Fig. 1 from sheetsteel of the desired thickness. 1 The stem A. immediately opposite the bit B. is prorided with the longitudinal slot 0, for the reception of the spline-blank D. The splinelank is fastened in the slot 0 by having its opposite edges-d d upset, whereby they are expanded and lap upon the sides of the stem, forming a double spline, as shown in Fig. 3.

Instead of having the splineproject from both sides of the stem A, it may, if desired, be made to project from one side only, as shown in Fig.

5, in which, as will be seen, the slot 0 is rep resented as having relatively-inclinedsides, and one edge, (1, of the spline-blank as being so upset as to just fill the slot C without pro 5 jecting therefrom, while the-other edge, ri is so upset as to lap over the edges upon the side of the stem, thus forming a single spline.

The key-hole bushing E is longitudinally recessed, as may be required, to admit the stem of the key, provided with a single or double spline. It will of course be understood that the spline may be secured to the stem by riveting in various Ways. Thus the spline may be made, as shown in Fig. 7, with two teats, F F, which may be inserted through two holes, ff, in the stem, and upset against the side a of the stem. By either mode of constructing and securing the spline the key will fit the key-hole bushing and be centralized therein by the spline.

I claim as my invention A flat steel key, in the stem of which, opposite the bit, there is formed a longitudinal slot, in which slot there is fastened a spline, one or both edges of which project from the side or sides of the stem, as and for the purpose set forth.

THOMAS LINCOLN. Witnesses:

FREDERIG ADAMS, TIMOTHY E. ScALEs. 

